1 Cent Coins

Die "scratches" are remnants of work done to the die to remove clashes ,small facial cracks , or other imperfections in the die face and are common. As far as the Legend shifting... Just not seeing what you mean.
Any "shift" of a design element other than the mintmark on pre 1990 modern era coins would be due to Die Deterioration or design changes.

looking again, what you may be seeing on your 84 is a MAD, Mis-aligned die , this is where the hammer die, in this case the obverse, isn't perfectly centered when the coin is struck. These only carry a premium if part of the design elements are missing.

The BU 80's cents that are heavily abraded look cool to me. I have an '85 or '86 somewhere, that has so many die scratches around Lincoln's profile, that it almost looks like a reverse proof if the light hits it just right.